Single Image Rollover
Start here to learn about Animated Rollovers. The single image rollover
is the starting block for all the other rollovers. View this demo
& its source. Then read the help files before trying the more difficult multiple
rollovers.

Multiple Position: Single Rollover
Here we use the same rollover images for all links. There are
multiple images on the page and we just turn "on" the
image that is to be highlighted. This saves on the number of images
that need to be downloaded (only 2 in this case).

Multiple Rollover: Single Position
Here we have a single image on the page but we swap different
images into it, depending on which link is being hovered. This
technique is used as a way to describe the links over which the
user is hovering.

Multiple Rollover
This combines the above link description technique with an image
rollover so the user knows which link is being hovered.

Multiple Rollover
If you really want to go overboard you can highlight the link
using all the above rollover techniques.